Portable air filter



FIG. 1 is a perspective view of the portable air filter of this invention;

FIG. 2 is a front view of the device of FIG. 1;

FIG. 3 is a top view of the device of FIG. 1;

FIG. 4 is a bottom view of the device of FIG. 1;

FIG. 5 is a back view of the device of this invention;

FIG. 6 is a right side view of the device of FIG. 1; and,

FIG. 7 is a left side view of the device of FIG. 1. 

The ornamental design for a portable air filter, as shown. 